Casing head



Oct. 13, 1931. I E. umm 1,827,287

CASING HEAD Filed Jan. 6, 1930 I ZSheets-Shea 2 I dwaraf 1T Guidinge bea tight seal between M m is. 1931 1,827,287

OF BARTLESVILLE, OKLAHOMA, ASSIGNbR TO PHILLIPS OF BARTLESVILLE,OKLAHOMA, A CORPORATION OF DELA- nnwann r. summers,

PETROLEUM COMPANY, WARE c emo HEAD Application filed January 6, eso.Serial, No. 418,863.

screws, etc., at the casing Another object is to furnish a casing headhaving a ground surface to contact with the corresponding surface of atubing hanger, and also provided with means for protecting said groundsurface to prevent mutilation of the same while the tubing is being fedinto the casin This invention relates to improvements in well equipment,and more especially to improvements in oil wells of the type employing acasing and tubing. To facilitate an understanding of the presentinvention, it may be well at the begmning, to explain the use of the twodifferent terms casing and tubing. An 011 well 1s nearly alwayscompleted for production with a string of steel pipe extending from thesurface of the ground to the top of-the oil sand, or near it. This pipeis called the well casing. When the well is to use a gas lift,anotherstring of smaller pipe, called tubing, is inserted through thecasing, the lower end of this tubing being placed wherever the wellfunctions the best from the standpoint of oil production and quantity ofgas required.

In some wells, the gas is admitted through the tubing and passes out atthe bottom through the oil, risingto the top of the well through thespace between the tubing and the casing. In other set-ups, the procedureis reversed,'the gas being injected into the well in the space betweenthe casing and tubing, mixing at the bottom withjthe 011, and themixture rising to the top through the tubing.- The-latter inthodiofhook-upis the one nearlfy always used in fields where the quality 0 theoil is such that there is a ten-- dency toward deposition of paraflin onthe walls of the flow column. In a set-up of this character, it is; notonly necessa that there with other objects 1n v1ew which will appear asthe description proceeds, the invention consists in the novel featureshereinafter described in detail, illustrated in. the accompanyingdrawings, and more particularly pointed out in the appended claims.

Referrmg to the drawings,

improved casing head and tubing hanger, and a portion of the welltubing.

Fig. 2 is a plan view of the casing head partly in horizontal-section,'the section being taken on the line 2'-2 of Fig. 3.

Fig. 3 is an elevation of the head, partly 1n vertical section, thesection being taken on line 3-3 of Fig. 3. v

Fig. 4 is a plan view of my novel tubing hanger.- I

. iFig. 5 is an elevationofthe saine,"partly in vertical section, on theline 5-5 of Fig. 4:.

By reference to the drawings, seen that an ordinary well casing 6 isprovided with internal threads that are engaged by external threads onmy casin head 8 thetubmg and the casing. at the well, mouth, but thesealingmeans should be simple, effective, and should lend itself. toaquick andbjasy'change in amount of tubing mythe'wel-lt, i. -lThe-primary object of. the present inven'- tion .isto' pro 'de such asealin means of a, novel type, 'and-one-which will relativelyinexpensive to. manufacture.-

Another object is to furnish such a sealing means, preferably comprisingonly two parts, one a packing head, and the other, a tubing piece ofmetal, such as steel, and it is of tubuar form, thelowerportion,beingprovided with the threads downwardly flared orfrusto-conical surface 9 on its interior. While the surface 9 may be ofany suitable inclination, I prefer to taper tively guides the tubing,(hereinafter referred to), as the latter is raised in, or withdrawn fromthe casing. v

The upper end of the surface 9 merges into a cylindrical surface 10,which extends upwardly on the inside of the head to an upanger.

A still further object is to provide a com.- bined casing head andtubing hanger, which will contact by means of ground surfaces, and

which will eliminate the use of packing, bolts,

head of the well.

With die foregoing'objects outlined and the section being taken Thishead is preferably formed'o a single the same about six and one-quarterinches per foot, as I have found that such a surface eflec- Fig. 1 is adiametrical vertical sectional new of the upper end of 'a well casing,my

it may be 7 on its exterior, and a taper of about ten inches per foot.This surface 11 acts as a protector for a frusto-conical ground sealingsurface 12, which is arranged above the surface 11, and preferably has aslightly different inclination from the latter.

surface. For example, the flared surface 12, may have a taper of aboutfourteen inches per foot.

It is highly essential that the surface 12 be protected from scarring ormutilation, and this is insured, not alone by the guide surface 11, butby an annular groove or channel 13, which is arranged within the head,and is located between the surfaces 11 and 12. As a further precaution,an annular recess or rabbet 14 is located in the head between the upperend of the surface 12 and. the horizontal top surface 15 of the head, toprevent any elevating means placed on the surface 15 from contactingwith or scarring the upper end of the surface 12.

The head terminates at its upper end in an annular flange 16, so as toprovide an enlargement on which the tubing elevator may rest, and belowthis flange, the head has the usual lateral screw threaded openings 17to be at tached to pipes that lead to or from the head.

This novel head cooperates with the tubing hanger 18, which is shown indetail in Figs. 4 and 5, and this hanger is also preferably made of asingle piece of steel, and is provided with a centrally disposedvertical bore, having internal screw threads 19 and 20. in order thatthe hanger may be interposed between two sections 21 and 22 of thetubing string and function as a joint in such string. To allow thehanger to be readily operated by a wrench, the threads 19 are formed inan upwardly extending boss'or nipple 23, having angularly arrangedsurfaces 24 on its exterior.-

Thelower portion of the hanger is provided with an externalfrusto-conical ground surface 25, which is tapered to conform with thesurface 12, and as the surfaces 12 and 25 are ground and snugly interfitwhen the hanger 18 is resting on the head 8. it will be understood thatthe weight of the tubing string will thus provide a sealed joint whichwill prevent the exit of gas.

In operation, the weight of the tubing, when resting on the taperedsurface 12, gives a perfectly tight seal. preventing loss of gas, butwhen it is decided to take the tubing out of the well, or run inadditional joints, it is only necessary to lift the string. of tubingwith the ordinary elevator and tubing blocks, whereupon the taperedtubing coupling 18 rises from the tapered seat 12, on the head, and canbe lifted up high enough to take the hanger 18 out of the string oftubing. After this is done, additional joints of tubaaaaeev ing may berun through the head, the couplings of such tubing passing freelythrough the bore of the hea As the tubing is moved into the well, thecouplings have a tendency to strike the tapered surface 12, which would,in time, prevent the proper seating of the head 18, and result in aleaky joint. To prevent this, the head has been provided. with thetapered guide surface 11 for the purpose of guiding the tubing tofacilitate the passing of the couplings thereof through the head. Therecess 14, during such operation, prevents any possibility of mutilationof the surface 12 by the tubing elevators, which rest on the top of thehead during the process of running tubing in, or out of the well. Bytaking the two precautions of shaping thelower surface.

11 as a guide for the tubing couplings, and the recess 14 at the upperend of the surface 12 to prevent mutilation, the latter surface, which,is the sealing ring, is practically assured of being kept free from anydamage.

So far as I am aware, there is no head made that will serve thispurpose, in as simple a way, and with as few parts as the head which Ihave devised. The ordinary head used, consists generally of a casinghead, a tubing support, and numerous glands, packing rings, slips,bolts, etc. Most of such heads must be taken off the casing in order toget additional joints of tubing in or out of the hole. Mv

improved head permits the free movement of the tubing with a minimumnumber of parts to be handled, and is very effective in its purose. PSome effor s have been made to provide heads capable of producing thesame results as mine, but mv head differs from them in at least threedifferent details. In the first place, the prior art heads have at theirlower ends, internal, instead of external threads. An external thread,such as shown at 7 in my drawings, is much cheaper to cut in the shop,and from that standpoint, more desirable.

In the second place, each of the prior proposals, while suggesting theuse of a tapered surface, shows only one tapered surface in the head forthe reception of the tubing collar, and also has packing of some sort.In one instance, it is proposed to wrap the tapered tubing collar with alaver of ead or similar sheet packing. and rely on the seal of thispacking to hold the pressure. In another case, it is suggested to cutgrooves in the tapered tubing collar or hanger in which are to be placedsquare hydraulic packing. thusrelying on the contact of this packingwith the tapered seat in the head for cutting off the pressure. In myhead, I rely solely on the fit secured by proper machining of both thetapered seat and the tapered collar for the pressure shut-off. Inpractice, I have demonstrated that if these tapered surfaces areproperly machined, and then ground to proposals differ from mine,

, occur by this .a fit, no difficulty is had in making a tight joint ifthe surfaces are perfectly clean when the tubing string is set down.

A third particular way in which the prior is that in the priorstructures, no provision is made for protection of the tapered seat in.the head, against abrasion from collars on the tubing string,

while being run through the head. It is obvious, as the tubing stringis'run into the casing, joint after joint being screwed into the topcollar, and the entire string being lowered into the hole through thehead, that the coupling collars will have a tendency to strike on oneside of the circular opening of the head. If these collars strike thesurface 12, some mutilation is to be expected, thereby preventing aperfect contact between the surfaces 12 and 25. In my head, I take careof this 'by providing the guide surface 11 on which the collars, as theypass into the hole, may strike-and be deflectedtowards the center of thehole, making it impossible for the collar to hang on any part of thehead as it passes through, and whatever mutilation may striking, is onthis guide surface 11. When the hanger 18 isset down, in order to effectthe shut-ofl:', the tapered sur face 25 on the tubing collar does notrest in contact with any part of the surface 11, but contacts only withthe surface 12, which has been arranged purposely for this contact. Asstated heretofore, the top edge of the surface 12 is turned off forabout half an inch below the flat top 15 of the head, and when elevatorswhich support the tubing strings by contact under a tubing collar, reston the flat top of the head 8, it is practically impossible for anymutilation to occur on the upper tapered surface 12. It will thereforebe seen that the surface 11 and the groove 14 insure the protection ofthe surface 12, so that the latte] may always-properly cooperate withthe surface 25 to make a perfect seal without the use of packing, boltsor the like.

Another advantage of my head over any of those on the market, resides inthe extreme simplicity of construction and assemblv, due to the factthat it consists of only two parts. Any head which involves the use ofsuch parts, together with packing, bolts, auxiliary flanges, etc., addsto the expense and diflicultv of equipping a well, ofttimes delayingwork or making the job more or less incomplete. These heads are usuallyupper portion of its bore,

construction, operation and advantagesof my invention may be readilyunderstood, and I am aware that changes may be made in the detailsdisclosed, without departing from the spirit of the invention, asexpressed in'the claims. 1

What I claim and desire to secure by Letters Patent is: v

1. A casing head comprising a metal tubular member having in the upperportion 0 its bore, an upwardly flaring ground contact surface, the borebeing provided with an annular recess-spacing the upper end of saidsurface from the top of the head, an upwardly flared guide surfacearranged below said contact surface, the bore having an annular groovearranged between the contact surface and the guide surface.

2. In combination, a casing head comprising a metal tubular memberhaving in the an upwardly flaring .ound-contact surface, the bore beingprovided with an annular recess spacing the upper end of said surfacefrom the top of the head, an upwardly flared guide surface arrangedbelow said contact surface, the having an annular groove arrangedbetween the 0011 act surface and the guide surface, and a tubing hangerprovided with an external ground surface conforming to and contactingwith the ground surface of the head.

In testimony whereof, I affix my signature.

EDWARD F. GUIDINGER.

installed on wells which have a'tendency to real advantage to use myimproved head which does not require any unusual effort to finish thejob. i

From the foregoing it is believed that the

